Gorman-Rupp Pumps 81 1/2D3-E.75 1P 252952 and up - Manual (Page 17)

TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
PUMP STOPS OR
FAILS TO DELIVER
RATED FLOW OR
PRESSURE (cont.)
PUMP REQUIRES
TOO MUCH
POWER
PUMP CLOGS
FREQUENTLY
Free impeller of debris. Impeller clogged.
Discharge head too low.
Dilute if possible. Liquid solution too thick.
Adjust discharge valve.
Open discharge valve fully to in-
crease flow rate, and run motor at
maximum governed speed. Discharge flow too slow.
EXCESSIVE NOISE Cavitation in pump. Reduce suction lift and/or friction
losses in suction line. Record vac-
uum and pressure gauge readings
and consult local representative or
factory.
Secure mounting hardware. Pump or drive not securely mounted.
Locate and eliminate source of air
bubble. Pumping entrained air.
Suction check valve or foot valve
clogged or binding. Clean valve.
Suction lift or discharge head too high. Check piping installation and install
bypass line if needed. See INSTAL-
LATION.
Impeller clogged or damaged. Clean out debris; replace damaged
parts.
Leaking or worn seal or pump gasket. Check pump vacuum. Replace
leaking or worn seal or gasket.
Low or incorrect voltage. Measure control box voltage, both
when pump is running and when
shut off.
No voltage at line side of circuit
breaker. Check power source for blown fuse,
open circuit breaker or control box,
broken lead, or loose connection.
Motor shaft or bearings defective. Disassemble pump and check mo-
tor and bearings.
OM−00752 80 SERIES
TROUBLESHOOTING PAGE D − 2